From owner-freebsd-bugs@freebsd.org Wed Dec 9 21:06:50 2015 Return-Path: Delivered-To: freebsd-bugs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 811E49D5EAC for ; Wed, 9 Dec 2015 21:06:50 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 59FB71BA0 for ; Wed, 9 Dec 2015 21:06:50 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id tB9L6o7S002096 for ; Wed, 9 Dec 2015 21:06:50 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 205163] Periodic jobs triggering panics on ZFS host with jails Date: Wed, 09 Dec 2015 21:06:50 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 10.2-STABLE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: dustinwenz@ebureau.com X-Bugzilla-Status: New X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-bugs@FreeBSD.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 09 Dec 2015 21:06:50 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=205163 --- Comment #3 from dustinwenz@ebureau.com --- I was checking out some of the variables as they are set at frame 7 (below). If it's to be believed, zfs_dirty_data_max_internal is much smaller than it should be at that point in the code (maybe due to memory corruption, or a race condition regarding zfs_dirty_data_max_internal). That would cause the subtraction at line 1079 to wrap to some value a bit less than uint64 max, but cast as a long long. I'm pretty sure that isn't how the code is intended to work. If that is a problem, disabling the vfs.zfs_dynamic_write_buffer tunable may help, because it should force zfs_dirty_data_max_internal to be the same as zfs_dirty_data_max. (kgdb) frame 7 #7 0xffffffff819f54d4 in dmu_tx_wait (tx=0xfffff805786ae400) at /usr/src/sys/modules/zfs/../../cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_tx.c:1078 1078 min_tx_time = zfs_delay_scale * (kgdb) list 1073 * cause a divide-by-zero if it's == the max. 1074 */ 1075 ASSERT3U(dirty, <, zfs_dirty_data_max_internal); 1076 1077 now = gethrtime(); 1078 min_tx_time = zfs_delay_scale * 1079 (dirty - delay_min_bytes) / (zfs_dirty_data_max_internal - dirty); 1080 if (now > tx->tx_start + min_tx_time) 1081 return; 1082 (kgdb) print zfs_dirty_data_max $1 = 3429452595 (kgdb) print zfs_dirty_data_max_internal $2 = 331001856 (kgdb) print dirty $3 = 336166912 -- You are receiving this mail because: You are the assignee for the bug.